what size should the output array be when pass reference to fft function? Image processing
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How can I calculate output array size for fft function? Im using swift 4 and Accelerate framework (func vDSP_fft_zop), but I think it is no matter. Also have question what difference if we use 1d and 2d array of pixels?
swift math fft accelerate-framework
asked Nov 20 at 0:50
Arkhyp Koshel
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favorite
How can I calculate output array size for fft function? Im using swift 4 and Accelerate framework (func vDSP_fft_zop), but I think it is no matter. Also have question what difference if we use 1d and 2d array of pixels?
swift math fft accelerate-framework
asked Nov 20 at 0:50
Arkhyp Koshel
989
add a comment |
up vote
0
down vote
favorite
up vote
0
down vote
favorite
How can I calculate output array size for fft function? Im using swift 4 and Accelerate framework (func vDSP_fft_zop), but I think it is no matter. Also have question what difference if we use 1d and 2d array of pixels?
swift math fft accelerate-framework
asked Nov 20 at 0:50
Arkhyp Koshel
989
How can I calculate output array size for fft function? Im using swift 4 and Accelerate framework (func vDSP_fft_zop), but I think it is no matter. Also have question what difference if we use 1d and 2d array of pixels?
swift math fft accelerate-framework
swift math fft accelerate-framework
asked Nov 20 at 0:50
Arkhyp Koshel
989
asked Nov 20 at 0:50
Arkhyp Koshel
989
asked Nov 20 at 0:50
Arkhyp Koshel
989
asked Nov 20 at 0:50
Arkhyp Koshel
989
asked Nov 20 at 0:50
Arkhyp Koshel
989
989
add a comment |
add a comment |
1 Answer
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Output array size is equal to input one: 1024 complex pairs give 1024 complex pairs.
Usually FFT works with sizes like 2^N (256, 1024, 2048 etc) (if data size is smaller - fill the rest with zeros), but some implementations could work with arbitrary sizes.
Data organization for 2d FTT might depend on implementation (for example, library FFTW for 2D requires array with [K+1][K] dimensions) so check documentation for clues
answered Nov 20 at 6:34
MBo
45.7k22848
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
0
down vote
Output array size is equal to input one: 1024 complex pairs give 1024 complex pairs.
Usually FFT works with sizes like 2^N (256, 1024, 2048 etc) (if data size is smaller - fill the rest with zeros), but some implementations could work with arbitrary sizes.
Data organization for 2d FTT might depend on implementation (for example, library FFTW for 2D requires array with [K+1][K] dimensions) so check documentation for clues
answered Nov 20 at 6:34
MBo
45.7k22848
add a comment |
up vote
0
down vote
Output array size is equal to input one: 1024 complex pairs give 1024 complex pairs.
Usually FFT works with sizes like 2^N (256, 1024, 2048 etc) (if data size is smaller - fill the rest with zeros), but some implementations could work with arbitrary sizes.
Data organization for 2d FTT might depend on implementation (for example, library FFTW for 2D requires array with [K+1][K] dimensions) so check documentation for clues
answered Nov 20 at 6:34
MBo
45.7k22848
add a comment |
up vote
0
down vote
up vote
0
down vote
Output array size is equal to input one: 1024 complex pairs give 1024 complex pairs.
Usually FFT works with sizes like 2^N (256, 1024, 2048 etc) (if data size is smaller - fill the rest with zeros), but some implementations could work with arbitrary sizes.
Data organization for 2d FTT might depend on implementation (for example, library FFTW for 2D requires array with [K+1][K] dimensions) so check documentation for clues
answered Nov 20 at 6:34
MBo
45.7k22848
Output array size is equal to input one: 1024 complex pairs give 1024 complex pairs.
Usually FFT works with sizes like 2^N (256, 1024, 2048 etc) (if data size is smaller - fill the rest with zeros), but some implementations could work with arbitrary sizes.
Data organization for 2d FTT might depend on implementation (for example, library FFTW for 2D requires array with [K+1][K] dimensions) so check documentation for clues
answered Nov 20 at 6:34
MBo
45.7k22848
answered Nov 20 at 6:34
MBo
45.7k22848
answered Nov 20 at 6:34
MBo
45.7k22848
answered Nov 20 at 6:34
MBo
45.7k22848
45.7k22848
add a comment |
add a comment |
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